Compound compression pump



Dec 25 1923.

F. S. CARVER COMPOUND COMPRESSION PUMP Filed Aug. 12, 1919 3 Sheets-Sheet 1 INVENTOR S /ZML /&

ATTORNEY Dec. 25 1923.

F. S. CARVER COMPOUND COMPRESSION PUMP Filed Aug. 12 1919 3 Sheets-Sheet 2 I INJENTOR (L/ ATTORNEY Dec. 25 {1923. 1,478,4Eig

F. S. CARVER COMPOUND COMFRES S I ON PUMP Filed Aug. 12, ,19l9 3 Sheets-Sheet 5 m if i 1' J 5 rnnn s. onnvnncr nnwnnn, a 1:;-

that

CQMPQUND COMPRESSION PUMP.

Application filed August 12, 1919. Serial 1%. 316,986.

To all whom it may concern."

Be it known that 1 Free S. CARVER, a citizen of the United tates, and a resident of Newark, county of Essex, and State of New Jersey, have inypnted oertain new and useful Improvements in Com und Compression Pumps, of which the ollowing is a specification;

My invention relates to compound compression pumps. One field in which it is of great utility is in compressing air for automobile tires, particularly the large truck tires which require an air pressure higher thancan be satisfactorily obtained by a single stage compression pump. The present application is a continuation in part of my prior application Ser. No. 240,629, filed June 18, 1918, entitled Compression pumps, patented June 13, 1922, $51,419,221.

in the drawings forming a. part of this s ecification, Fig. 1 is a central, vertical sec tional view of a pump embodying my invention. Fig. 2 is a. sectional view taken on the line 22, Fig. 1. Fig. 3 is a vertical sectional view taken substantially on the broken line 3-3, of 'Fig- 1. Fig. at is a plan view of the bottom plate for the oil chamber in the pum base. Fig. 5 is a side view of the plate 0 Fig. d with arts broken away. Fi 6 is a cross sectiona detail view on an en arged scale, showing a valve and its mounting. Fig. 7 is a. pers ective view with parts broken away of a va ve disc. Figs. 8 and 9 are diagrammatical sectional views arranged to show the operation of the a paratus Fig. 8 being substantially on t e broken ine o-b-c, of Fig. 10 and Fig.9 being taken substantially on the broken line d-b-c of Fig. 10, the sections so obtained being shown 0 ened out in Figs. 8 and 9 for the purpose 0 more clearly illustrating the operation of the apparatus. Fi 10 is atop view of the cylinder casting. lg. 11 is a ira entary side view of a portion of the cylinder casting and showing one of the gar-d plates for the air inlet passages, and

ig. 12 is a detail view showing a mode of attaching an extra supporting member for the pump to give a three-point support.

The cylinder casting 10 is preferably pro vided w th heat conducting ribs 10' and contains the low pressure cylinder 11 and the hi h pressure cylinder 12, arranged side by si e and parallel to one another. Cylinders 11 and 12 receive pistons 18 and 14:, the piston rods 15 and 16 whereof project upwardly beyond the cylinders 11 and 12. Upon the cy inder casting 10 is secured the hollow casting 17. The base of casting 17 closes the upper ends of cylinders 11 and 12. The piston rods 15 and 16' pass through openinin the base of casti 17 and project into interior thereof. ubstantially air tight glands are provided about piston rods 15 and 16, as by means of packing rings 18 and screw rings 19, which when screwed in place in screw threaded rec 20 serve to compress the packing rings 18.

The hollow casting 17 contains the actuat 1n devices and also contains an oil bath for In ricating purposes.

The upper ends of the piston rods 15and 16 are connected within casting 17 by a combined cross head and Scotch yoke member 21 to which said piston rods are secured in any desired way, as by means of pins 22 holding the ends of the rods in suitable sockets in member 21. The yoke member 21 is preferably provided with a downwardly extending projection 23, which enters the oil pocket 24- and serves to efiectively splash the oil on the workin parts, even though the uantity of oil should be greatly reduced an the oil level quite low. The yoke member 21 is pro vided with an opening 25- in which the cam 26 works, and wear plates .27 are provided at the upper and lower ortions thereof. Same may be removable, i desired, so that the can be renewed to compensate for wear at ong intervals. lo 25 is preferably large enough to clmr the cam 26 except at the regions occupied by wear plates 27. The bearings for the cam shaft 28 and also the guides for the Scotch oke member 21 are preferably formed in t e discs or plates 29 which are secured to-the casting 17 as by bolts 30 around openings 31 provided in opposit/e sides of the casting 17. These plates or discs 29 are preferably of identical form for the two sides of the pump, and are interchangeable, and so can be conveniently made in quantities, quirin only a. ..single set of jigs, fiatures and the li e. -$aidplates 29 are provided with guide means for the Scotch yoke. In the form shown, the yoke 21 is provided on each side and at top and bottomwith laterally extending guide lugs 32, which are received and guided 1n grooves 33 formed on the interior of "the plates or discs 29. Discs 29 have the central openings 34; therein in which the bushings 34' for the cam shaft 28 are driven, and felt washers shaft are readil as for example, where the pump is attached.

to a truck engine, and the space is limited.

It will be apparent that the cam and cam reversible from the position shown, an the pum can be driven from either side and in eit er direction.

The arrangement of the airpassa as from cylinder to cylinder and out at the discharge opening is substantially as shown in my former application above referred to. There are six check valves, designated respectively A, B, C, D, E and F. The air enters the upper end of the low pressure cylinder 11 through check valve A. The air compressed beneath the piston 13 in the low pressure cylinder 11 passes out back of the check valve B through the check valve C and into the upper end of the high pressure cylinder 12. The air compressed in the lower portion of the high pressure cylinder 12 passes out through check valve D past valve F and thence to the tire or other air container. as will be plain on reference to Fig. 9. Re-

ferring to Fig. 8 it willbe seen that the air enters the lower end of the low pressure cylinder 11 through check valve 13, the air compressed in the upper end of the cylinder 11 passes out back of check valve A and through check valve E, entering the lower portion of the high pressure cylinder 12, and the air compressed in the upper portion of the hi h pressure cylinder 12 passes out throng the check valve F to the pressure receptacle or-container. As such arrangement of valves has already been described in my former application, further reference thereto here is unnecessary.

I rovide means for preventing ingress of dirt, dust and the like with the inlet air by shielding the assages therefor and straining the air as 1t is admitted. The incoming air is referably passed through a wire gauze or t e like strainer, as indicated at 38, 38 in Fig. 3 and the air inlets are further guarded by plates 39, 39 havin air inlet openings 40 which may be forms by punching out portions 41, 41 from the sheet reverse metal, such. punched out portions having substantially the form of louvres which exi tend downwardly over the openings 40, directing any material, such as dirt,water, or the like, downwardly and away from the inlet opening 40.

I have provided metal valves of such form as to be highly eiiective, and not readily get out of order or leak over extended periods of use. The preferred form of valve and mounting therefor is shown in detail in Figs. 6 and 7. The valves have the form of discs 45 having depressed or thinner central portions 46, and marginal thickened or upstanding portions 47. The two'sides of the valve are alike so as to require no attention in assembling to see that the right side is up.

. The valve seats preferably have projecting annular seating surfaces 48 as shown in Fi 6, and a clearance depression 49; is rovi ed therearound. The valves are hel to their seats by springs 50, the ends of the springs adjacent to the valves being received within the recessed portions 46 as shown in ft will be seen that a valve of the construction described has a number of advantages which are of the utmost importance in the heavy work to which a. pump is subjected, for example, on a truck, pumping up heavy pneumatic tires of lar e diameter. The

valve surfaces are entire y of metal, and the wear is not localized, but the valve may move freely within the seat opening 51 which is of greater diameter than the overall diameter of the valve disc 45 permitting same to move freely from side to side on its seat as it is opened and closed, thereby preventing the localizing of wear on the seat and valve face and providing a practicall foolproof valve construction which wi 1 stand up in use over extending periods when subjected to the severest treatment. The valve being all metal is not aiiected by heat as valves includin leather, fibre and the like may be. The va ve springs 50 are preferably received within guide sleeves 52 upon the ends 53 of which the valves 49 may rest when opened as shown in Figs. 8 and 9, for example, thus limiting the opening movement of valves 45 and servmg to assist in keeping same in proper alignment and position. With such arrangement the valve discs rechain at all times substantially parallel to their seats and cannot be turned on edge or otherwise gotten into improper position.

The oil from the chamber 24 passes-gradually down into the pump cylinders along the piston rods and serves to lubricate the pistons, and means are preferably provided for separating oil from the air discharged from the ump, so as to prevent injury to tires, whic might be can b oil.

In the form shown, I provi e a separator plate-54 between the air discharge outlet 55 incense from the pump cylinders and the tube 56 leading to a tire or other container.

For greater certainty of preventing ingress of foreign materia into the tire or its valve a strainer 57 is provided for the outgoing air and formed of wire gauze or other suitable material. Below the separator plate 54 an oil well is provided and the same is formed in a separate late or under cover 58 shown enlarged in igs. a and 5. Th s plate is substantially of cup form. It 18 provided with apertured ears or lugs 59 by which it may be bolted in place in a plurality of difi'erent rotative positions. It has a pair of crossing ribs 60, 60, oneoi which extends below and substantially parallel to the separator plate 54 in an rotative position of cup 58 and prevents t e air sweeping freely along thebbttom of the cup and carrying the oil out with it. A hole 61 1s bored centrally upward from the bottom of the on shaped member 58 and part way throng the ribs so at their intersection and is tapped for a plug or draw ofi cook 62. A side hole 63 is provided bored through under one of the ribs 60 and tapped for a draw ofi cock or plug 64. it will be seen that the opening 61 provides communication between the various corner kets formed within the cup shaped member 58, so that a draw-ed cock connected with either the o ening 61 or the openin 63 will serve to e ectively drain the oil lrom the interior of the chamber and from all parts or pockets thereof. When not convenient to put a draw off cock at the bottom as by reason of laclr of room, the bottom opening can be plugged and the draw ofi cock ut in the side opening 63, and substantial y as good results obtained as with a draw ofi cock in the bottom. The draw ofi' cock is opened from time to time, to discharge any oil which may have, accumulated in the separa- 'tion chamber.

Bolt holes 65 are provided on each side of the pump for securing it in place. As already stated, the pump ma be driven from either side and similarl it may be bolted in place from either si e as may be most convenient. A three point connection can be obtained by making one of the bolts for plate 29 longer than the rest and passing it through a suitable strap or other supporting means 66, as shown at 30, Fig. 12.

t may be seen that a pump in accordance with my invention has numerous advan tages: It is compact, is readily manufactured and assembled, it can be connected in many ways to suit-varying conditions, the valves, pistons and actuating mechanism are thoroughly lubricated and of such structure as not to require attention over long intervals, dirt is kept out, and oil is separated and preventedfrom reaching the tires.

, casin Tl cla: v L In a p mp, a cylinder containing mem ber, pistons and piston rods for the cylin- I ders, a hollow member secured to the first named member and into which the piston rods project from the cylinders, a combined cross-head and Scotch yoke and a rotatable actuating device therefor in the hollow member, and a pair of oppositely positioned plates secured about openings formed in the hollow member and containing bearings for the rotatable actuating device, and oiding means carried by the plates to guide the Scotch yoke member in rectilinear movement.

2. In a pump, a plurality of cylinders, pistonstherefor, piston rods on said pistons, a combined cross-head and Scotch yoke attached to said piston rods, a shaft having an eccentric therein. for actuating said Scotch yoke, and guide meansv for the Scotch yoke, arranged on the side thereof, and in substantially the same plane with the axis of the shaft. 1

3. In a pump, a shaft, an eccentric there on, a Scotch yoke actuated from the said eccentric, a plurality of pistons and their cylinders, all the pistons being attached to the same side of the Scotch oke, and a pair of members containing the shaft and each of said members being provided with guide means for the Scotch yoke.

43:. in a pump, a pair of high and low pressure c hinders arranged parallel and side by si e, pistons and piston rods for sald cylinders, a Scotch yoke to which the piston rods are rigidly connected, an eccentric turning in said Scotch yoke on an axis at right angles to the plane of the piston rods, and arranged substantiall midway between the piston rods, and guides on opposite sides oil the Scotch yoke and at substantially the middle thereof for fluiding the Scotch olre and piston ro to move rectilinear y, the cam being tioned between the cylinders and guides.

5. In a pump, a plurality of cylinders arranged side by side and parallel pistons and piston rods for the cylinders, a hollow containing an oil bath into which the piston rods project, a cross-head therein to which the istons are ri idly secured, oppositely positioned remova le plates secured to said casing, rotary means in said hollow casing for impartin reciprocatory movement to said cross-hes and pistons, a pair of guide lugs on each face of the crossead, and guideways formed in the plates for receiving and guidin said lugs and thereby confine the crossmad and pistons to rectilinear movement. i 6. in a pump, high and low pressure cylinders, a pair of pistons for said cylinders,

the

arings torposi ' avaaeo a Scotch yoketo which said pistons are secated, said oil bath being above the pistons cured, both on the same side of the Scotch and adapted to supply oil thereto, and an 10 yoke, an eccentric on its shaft for driving oil separator on. the discharge side of the said Scotch yoke and pistons, guide means pump and located below the pistons.

on the sides of the eccentric substantially In testimony that I claim the foregoing in. the same plane with the axis of the ec 1 hereto set my hand, this 11th day 0 centric shaft for guiding said Scotch yoke, August, 1919.

an oil bath wherein said Scotch yoke 1s lo- FRED S. CARVER. 

